The paper presents the results of numerical modeling of hot spot growth process in detonation with account for turbulent mixing. The performed investigation has shown that large-scale HE （High explosives） particles ...The paper presents the results of numerical modeling of hot spot growth process in detonation with account for turbulent mixing. The performed investigation has shown that large-scale HE （High explosives） particles mix up and split down to smaller sizes in the result of shock wave impact, instability development on the HE-EP （Explosion product） interface and vortex flow; at these sizes, due to the developed surface of the HE-EP contact, HE has enough time to get heated （energy transfer from EP）, and the decomposition reaction effectively continues. Numerical modeling make the calculation of the hot spot growth rate （about 100-200 m/s） possible. This has proved the hypothesis saying that at mechanical material transport the turbulence in the reaction zone plays an important role and it must be taken into account in the detonation theory.展开更多
A 3D t＇mite element model of the explosive welding process of three-layer plates with materials of steel-copper-copper is es- tablished. Based on the presented model, the bonding mechanism is simulated and analyzed, ...A 3D t＇mite element model of the explosive welding process of three-layer plates with materials of steel-copper-copper is es- tablished. Based on the presented model, the bonding mechanism is simulated and analyzed, different detonation modes are also comparatively studied to indicate the driving force spread in few microseconds. The results show that the three layer plates bond together after many times of impact between the flyers and the base driven by detonation wave, which is damping rapidly at each impact with wavelength decreasing. The pressure at the detonation point is minimal, which induces non-bonding of the plates here. Detonation wave propagates in concentric circle both under side-midpoint detonation mode and under center-point detonation mode, but the movement of the flyer is different, which makes non-bonding easily occur at the end of detonation under side-midpoint detonation and at the center of the plate under center-point detonation.展开更多
文摘The paper presents the results of numerical modeling of hot spot growth process in detonation with account for turbulent mixing. The performed investigation has shown that large-scale HE （High explosives） particles mix up and split down to smaller sizes in the result of shock wave impact, instability development on the HE-EP （Explosion product） interface and vortex flow; at these sizes, due to the developed surface of the HE-EP contact, HE has enough time to get heated （energy transfer from EP）, and the decomposition reaction effectively continues. Numerical modeling make the calculation of the hot spot growth rate （about 100-200 m/s） possible. This has proved the hypothesis saying that at mechanical material transport the turbulence in the reaction zone plays an important role and it must be taken into account in the detonation theory.
基金supported by the State Key Laboratory of Solidification Processing in Northwestern Polytechnical University (Grant No. SKLSP200906 )111 Project (Grant No. B08040)
文摘A 3D t＇mite element model of the explosive welding process of three-layer plates with materials of steel-copper-copper is es- tablished. Based on the presented model, the bonding mechanism is simulated and analyzed, different detonation modes are also comparatively studied to indicate the driving force spread in few microseconds. The results show that the three layer plates bond together after many times of impact between the flyers and the base driven by detonation wave, which is damping rapidly at each impact with wavelength decreasing. The pressure at the detonation point is minimal, which induces non-bonding of the plates here. Detonation wave propagates in concentric circle both under side-midpoint detonation mode and under center-point detonation mode, but the movement of the flyer is different, which makes non-bonding easily occur at the end of detonation under side-midpoint detonation and at the center of the plate under center-point detonation.
